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Wednesday, November 26, 2014

The McKinsey Global Institute produces a series of discussion
papers funded solely by the McKinsey partners and very recently, they released
a report entitled “Overcoming obesity: an initial economic analysis”. The
report is divided into two main sections, one dealing with the economic burden
of obesity and one dealing with the possible interventions to mitigate the
economic costs of obesity. For anyone interested in the subject, I strongly
advise accessing the PDF, which is available free[1].

The first point they note is that obesity does not appear to
be correlated with a country’s wealth. Malaysia, Thailand and China have a much
lower GDP per head of population than Hong Kong, Japan and South Korea and yet
they have the same rates of obesity (5-15%). Equally, Japan, South Korea and
Hong Kong have one-third the obesity rates found in Saudi Arabia, the US and UK
(30-35%) and yet they share the same GDP/head/year. Developing countries have
obesity rates that are just 25% that of developed nations but their rate of
annual increase in obesity levels are much higher that developed countries
(+90% v. +17%).

The report examines 14 major global problems which are
largely man made or are amplified by human decisions. Top of the list is
smoking with an annual cost of US$2.1 trillion. Armed violence, war and
terrorism share joint first place with tobacco and in third place comes obesity
with an annual cost which is just marginally less at US$2.0 trillion. The first
two each occupy 2.9% of global GDP while obesity occupies 2.8%. Taking the UK
as an example, the report shows that obesity costs the taxpayer a staggering stg
£10 billion annually, which is 5% of the total National Health Service (NHS)
costs. But they do express this figure differently with shocking effects. This
stg £10 billion on obesity equals the combined
costs of the UK police force, fire services, law courts and prisons!!!

In terms of tackling obesity, the report rightly argues at the
outset of this section that: “Obesity is
the result of a multitude of factors, and therefore no single solution is
likely to be effective in tackling it. A range of interventions that encourage
and empower individuals to make the required behavioural changes will be
necessary. These interventions need to be systematic, not only aiming for an
immediate impact on the net energy balance but also making sure that change is
sustained”. Music to my ears! However, it is clear that despite the
moanings and groanings of ministers about the terror of obesity, investment in
prevention is abysmal. The report estimates that we would need a global
investment of US$ 5 billion, which is just 0.25% of the global cost of obesity.
The same percentage figure for road traffic accidents is 5 times that of
obesity.

The report identified a total of 74 possible interventions,
which they reduced into 18 groups and the list is as follows: Active transport;
Health Care Payors; Healthy meals; High calorie food and drink availability;
Labelling; Media restrictions; Parental education; Pharmaceuticals; Portion
control; Price promotions; Public health campaigns; Reformulation; School
curriculum; Subsidies, taxes and prices; Surgery; Urban environment;
Weight-management programmes; Workplace wellness. The study examined over 500
research studies and they used the Level of Evidence System of the Oxford
Centre for Evidence-Based Medicine. They have some caveats about their analysis
and point out that this is the first in a series of reports on this topic. They
word this reservation very nicely: “The
conclusions we draw on an integrated response to obesity should be viewed as
the equivalent of a 16th-century map of the world; some islands may
be missing and the shapes of continents somewhat skewed, but it is
directionally correct.”

If the 16 responses that are amenable to economic
quantification were to be enacted in the UK, they would expect that this would
halt rising obesity and indeed reverse the obesity prevalence by 20% within 5
to 10 years. They rank the impact of each response in a cost effective way
using the standard expression of Disability Adjusted Life Years (DALY). The top
three are (1) Portion control with a DALY value of 2,126, (2) Reformulation
with a DALY value of 1,709 and (3) High calorie food/beverage availability with
a DALY value of 1,137. Interestingly, they also examine how these rankings are
linked to media coverage using UK data. It makes interesting reading. Portion
control with a DALY value of 2,126 had just 182 media coverage while a 10% tax
on high sugar high fat products with a DALY value of just 203 had over 930
press citations.

Thus far in the McKinsey obesity journey, the map tells us
where we get most bang for our buck but most importantly, it tells us that ALL
areas need to be simultaneously acted on to have any benefit. The day will come
when flesh has to be put on some of these responses and here I have a problem.
The top ranked solution is portion control and in reading the report there is
discussion of how companies are going to move in this direction: Do they all do
it together or will there be “leaders”? Now, this morning, I had porridge for
breakfast and I determined how much porridge to put in my bowl and how much and
what type) milk and sugar I’d put on the cooked porridge. For lunch I had home
made soup and bread and I determined the size of soup bowl, the quantity of soup
to consume, the number of slices of bread and the amount and type of spreadable
fat to use on the bread. This evening, I’ll dine with my youngest daughter and
my eldest granddaughter in an Italian restaurant and while I’ll have no
control, more or less on portion size, I myself will decide on how much to eat
and how much to leave. Regulating the portion size of snack bars is easy.
Regulating the portion sizes majority of the foods we eat at home is an
entirely different challenge. We need somehow to create an environment where
large portion sizes are anti social. Taxes have played a huge role in tackling
smoking but this was associated with an aggressive and well funded public
health single-issue campaign against smoking. New data suggests that the anti-social
aspect of smoking was every bit as powerful as taxes[2]. Taxes
will be lees effective in directing food choice but energy intake can be
reduced by adopting new social norms to serving sizes and eating behaviour in
general. How to achieve this is the massive challenge. Smaller plates? Let’s
put a tax on plate size!!!!!! Well done McKinsey.

Wednesday, November 5, 2014

Just three weeks ago,
the headlines of a popular British newspaper carried the banner headline on its
front page linking fruit juice consumption with elevated blood pressure. It was
based on a study reported in the generally well-regarded scientific journal
Appetite and was conducted by researchers in Australia[1].
The sample was small, just 146 subjects and their diets were analysed using a
food frequency questionnaire. The authors created three groups according to
their intake of fruit juice: “Rarely”, with fruit juice intake ranging from 0
to less than 3 times per month, “Occasionally” ranging from once per week to
5-6 times per week and “Daily” corresponding to once per day to more than 3
times per day. They examined blood pressure using two techniques that measure central
blood pressure and brachial blood pressure. The authors found no statistically
significant effect of fruit juice consumption on brachial blood pressure but
they did find a statistically significant effect of fruit juice intake on
central blood pressure (systolic only). The authors in their discussion note
that this is the first study to examine the link between fruit juice
consumption and hypertension and it should be noted that they do associate
fruit juice intake with fructose intake. They go on to say: ”These findings are important as there is a
common perception that fruit juice is healthy” and they continue, thus: “Thus, frequent fruit juice consumption may
be contributing to excessive sugar intake, typical of the Western population,
exacerbating the prevalence of hypertension.”

Now lets pause here
for a minute, because this is quite a sensational claim. The authors have not
examined total sugar intake in their study so they themselves cannot imply that
higher fruit juice intake is associated with higher sugar intake. What about
sugar from the sugar bowl, from jams and preserves, biscuits and cakes and of
course soft drinks? In the absence of data on total sugar intake, the authors
can conclude nothing whatsoever. The authors never mention this fact when they
consider the limitations of the study. Rather, they regret that they were not
able to statistically control for “total energy intake or total calories” (the
same thing by the way). But they were able to control for weight height and
other potentially confounding factors. Why could they not control for energy
intake? To fail to report total energy intake and the fraction of that intake
contributed by total sugar and added sugar is unfathomable in terms of
scientific rigour. It renders this paper utterly useless and it casts a shadow
on the editorial process of the journal where it was published. But it made
great headlines and no doubt the Daily Mail story was carried around the world
to warm the cockles of the beating hearts of the “sugar is toxic” school of
thought.

Now contrast that
paper with one published about the same time by a consortium led by David
Jenkins a Canadian based world leader in the field of diet and health[2].
This group conducted a systematic review and meta analysis of studies, which
have measured actual fructose intake and followed the subjects up for many
years to monitor the development of hypertension. They identified 3,749 scientific
papers with the words “fructose” and “hypertension” in the titles and immediately
scrapped 3,723 because they were animal studies, cell studies, case studies,
reviews rather that actual studies and so on. Of the 26 articles remaining, 25
were omitted because they had inadequate end-points (14), were a
non-prospective (follow-up) cohort (7) or did not disclose total fructose
intake (3). Theses omissions were all based upon strict rules that are
internationally regarded as the “must follow” rules of systematic reviews. That
left them with just three studies. However, these were very big studies, which
involved 223,230 subjects who were perfectly healthy when recruited at
baseline. They were followed up for an average of 11 years and 58,162 went on
to develop clinical hypertension.The
subjects were categorized in to (fifths) quintiles of fructose intake. The
authors found absolutely no evidence that the greater the quantity of fructose
consumed from the lowest to the highest fifth was in any way associated with
hypertension. The statistical models included all known confounding factors.

It should be noted
that all three of the above papers were in the literature for the Australian
group to go and find but apparently, they did not. The “sugar is toxic”
die-hards will remember their study. But the scientific world will remain far
more impressed by the Jenkins systematic review.

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"Ever seen a fat fox ~ Human obesity explored"

About Me

I graduated from University College Dublin in 1971 with an Masters in Agricultural Chemistry, took a PhD at Sydney University in 1976 and joined the University of Southampton Medical School as a lecturer in human nutrition in 1977. In 1984 I returned to Ireland to take up a post at the Department of Clinical Medicine Trinity College Dublin and was appointed as professor of human nutrition. In 2006 I left Trinity and moved to University College Dublin as Director of the UCD Institute of Food and Health. I am a former President of the Nutrition Society and I've served on several EU and UN committees on nutrition and Health. I have published over 350+ peer reviewed scientific papers in Public Health Nutrition and Molecular Nutrition and am principal investigator on several national and EU projects (www.ucd.ie/jingo; www.food4me.org). My popular books are "Something to chew on ~ challenging controversies in human nutrition" and "Ever seen a fat fox: human obesity explored"